Numerous types of equipment used for the analysis or purification of chemical compounds utilize miniature fluid conduits, such as metallic tubing, within which liquid samples pass through the system. For example, liquid chromatography is a technique in which a column is packed with a packing material, an analyte is introduced into one end of the column, and a carrier fluid is then run through the column. The length of time that the analyte is retained within the column can enable analysis and identification of the analyte. A popular form of liquid chromatography is High Performance Liquid Chromatography (HPLC) in which the sample is pumped through the column under an elevated pressure, typically at 300 to 6,000 psi.
Liquid chromatography systems, such as HPLC systems, typically include several components, for example; a pump; an injection valve for injecting the analyte; a precolumn filter to remove particulate matter in the analyte solution that might clog the column; a guard column to retain irreversibly adsorbed chemical material; the HPLC column itself; and a detector that analyzes the carrier fluid as it leaves the column. These various components may typically be connected by a miniature fluid conduit, such as metallic or polymeric tubing, usually having an internal diameter of 0.005 to 0.040 inch. All of these various components and lengths of tubing are typically interconnected by threaded fittings. Often, a first internally threaded fitting seals to a first component with a ferrule or similar sealing device. The first fitting is threadedly connected through multiple turns by hand or by use of a wrench or wrenches to a second fitting having a corresponding external fitting, which is in turn sealed to a second component by a ferrule or other seal. Disconnection of these fittings for component replacement, maintenance or reconfiguration again requires the use of a wrench or wrenches to unthread the fittings. Most thread connections are 10-32, 1/4-28 or 6 mm.times.1. If a hand-tightened threaded fitting is used, it may not stand up to the extreme pressures of HPLC.